ADRIFT ON THE GREAT LAKE OF UNKNOWING:
THE FLOTATION TANK

THE CASE OF THE INCREDIBLE DISAPPEARING BODY

Since your ears are underwater and stopped with plugs, there is also an almost total absence of external sounds, another experience with no counterpart in ordinary life situations. With this turning off of both sight and sound, the float tank matches the blank-out effect created by the unchanging ganzfeld and pink noise of the Tranquillity. However, the tank goes beyond this by restricting stimuli reaching other senses as well. The warm water of the tank is maintained at a constant temperature of about 93.8 degrees, which is equal to the body's temperature at the skin surface - there is no feeling of either warmth or cold, so that you soon lose any sense of separation between skin and water, and the boundaries of your body seem to dissolve, effectively creating a blank-out of the sense of touch, pressure, friction, and other skin sensations.

Another sensation floating turns off is the usually ever-present pressure of gravity. In the words of the tank's inventor, neurophysiologist Dr. John Lilly, "You're free of gravity; you don't have any more of those gravity confrontations that you do all day long. Finding where gravity is, and in what direction, and computing how you can move and not fall takes up about 90 percent of your neural activity. As soon as you start floating you're freed of all the gravity computations you've been doing all the time, so you find you have a whole vast piece of machinery that was being used for something else and you can now use it for your own purposes... It's as if you are somewhere between the moon and the earth, floating, and there is no pull on you. As soon as you move, of course, you know where you are, but if you don't move your environment disappears and, in fact, your body can disappear."

The tank, then uses technological means to quickly, easily, reliably, and safely produce the turning off of the senses that all the meditative techniques such as breath-counting, chanting, repetition of mantras, and focused gazing strive for but so rarely attain. Even first-time floaters find that within minutes they are suspended weightlessly, without a body, in a totally black, silent void.

And unlike meditative techniques, which are so numerous and have so many variables that it is difficult to subject them to large-scale, objective, controlled, repeatable scientific studies, the flotation tank is a controlled and unchanging environment, ideally suited for scientific research. Attempts to study meditation often must compare groups of subjects engaged in specific meditative techniques with control groups who are (usually) simply sitting quietly. But as we have seen, it is often hard to tell if meditators are truly in an authentic meditative state. However, when using the tank, there can be no doubts which group is floating and which is not. The result is that float-tank research produces those things so dear to the scientific heart-hard data, value-free statistics, replicable objective studies. As a consequence, there has been a surge of flotation-tank research in recent years by large numbers of scientists interested in the workings of the human mind, including cognitive psychologists, neuroendocrinologists, educators, and psychiatrists. These researchers have produced a comparatively large body of information about the effects of flotation and sensory deprivation. Among their findings:
 

STRESS REDUCTION

So it's of enormous importance that a large amount of research, particularly several series of studies at the Medical College of Ohio, Lawrence College, St. Elizabeth's Hospital in Appleton, Wisconsin, and the University of British Columbia, demonstrate that floating has a dramatic stress- reduction effect. Among the findings are that periodic floats reduce heart rate, oxygen consumption, and the levels of stress-related biochemicals in the bloodstream, including cortisol, ACTH, lactate, and adrenaline. The studies show that floating not only reduces these biochemicals during the float period, but also keeps the levels low for days and in some cases weeks after the float session. Because of an apparent vasodilatory effect (that is, blood vessels and capillaries are caused to relax and dilate), floating not only reduces high blood pressure but speeds and increases the flow of blood, with its oxygen and other nutrients, to all parts of the brain. We can speculate that this increased flow of blood to the brain enhances mental functioning and assists in building new brain tissue and nourishing neurons, leading to greater dendritic length, increased richness of dendritic connections, and increased thickness and weight of the neocortex. An enriched flow of blood is essential to protein synthesis, and since recent findings by neuroscientists have shown that memory formation is dependent on protein synthesis in the brain, we can also speculate that this blood-enrichment effect of floating enhances memory formation.
 

INCREASED TOLERANCE FOR STRESS

In light of this, it's significant that studies by neuroendocrinologist John Turner and psychologist Tom Fine at the Medical College of Ohio indicate that floating not only significantly reduces the levels of stress-related biochemicals, but also has what Turner and Fine call a strong "maintenance effect" - the lowering of the stress biochemicals continued for many days after the subject's last float. This has led them to conclude that floating can "alter the set points in the endocrine homeostatic mechanism so that the individual would be experiencing a lower adrenal activation state. It would essentially be associated with a greater degree of relaxation".

This is striking, since it means that the beneficial effects of floating are not just temporary, but alter the metabolism (or homeostatic set point), essentially damping down the fight-or-flight response. This means that levels of pressure that might once have disrupted your ability to think clearly and perform effectively will seem less stressful after floating. That is, floating is a way of increasing our tolerance for stress.
 

DEEP RELAXATION

But good relaxation is hard to find. Relaxation techniques such as Progressive relaxation, Autogenics, and meditation take effort and discipline, with no assurance of success. In fact, many authorities now believe that most of us have never experienced complete relaxation in our lives, so we have no real conception of what it feels like, and no idea of how to cause our bodies to create that state.

In the warm Epsom salts of the float tank, however, free from the tug of gravity, your muscles unfold like Chinese Paper flowers in water, growing supple and pliant. Several studies have used an electromyograph (EMG), which measures muscular tension, to compare groups who simply floated with groups of nonfloaters who relaxed by using various relaxation techniques. In every study floaters quickly became far more deeply relaxed than the nonfloat groups. Significantly, this reduction in tension persisted, according to one study, for up to three weeks after a float.

In fact, all evidence indicates that floating actively and automatically triggers the mirror image of the fight-or-flight response, the relaxation response. This reflexive response includes reductions in heart rate, blood pressure, alterations in brain-wave, muscular relaxation, decreased oxygen consumption, decrease in stress-related biochemicals, and increased secretions of biochemicals that fill the body with a sense of well-being, pleasure, safety, and mental clarity. If the fight-or-flight response is one of spending energy and acting, the relaxation response is one of saving energy and thinking. Research indicates that floating activates this healthful response effortlessly. According to Fine and Turner of the Medical College of Ohio: "These (other relaxation) techniques have the individual elicit relaxation utilizing some internal strategy with or without external feedback as to the success of the strategy. In contrast (floatation tank) relaxation utilizes an environment to induce relaxation with the individual passively experiencing the process... The controlled repeated experiences of this effortless passive relaxation provided by the tank may provide an advantage over these other methods requiring a trial and error approach to the deep relaxation state."
 

PUMPING ENDORPHINS

INCREASED THETA PRODUCTION

INCREASED ACCESS TO THE RIGHT HEMISPHERE

HEIGHTENED SUGGESTIBILITY

Another explanation is the "stimulus hunger" effect - in the absence of external stimulation, the RAS "turns up" the brain's volume control and the brain becomes '"hungry" for information. So when it's given a message, it accepts it totally. Another explanation is that the part of the brain in charge of reality testing, critically evaluating incoming information, is turned off in the restricted stimulation environment of the tank, so messages can bypass the usual censor of filter and enter directly into the subconscious. In fact, Dr. Lloyd Glauberman, a New York City therapist with many years of experience in the use of hypnosis, who is now using float tanks equipped with in-tank speakers for training athletes and altering behavior patterns, told me that "the float tank is much more powerful than hypnosis - simply floating, without inducing a trance, makes you more suggestible than hypnosis." Studies at the University of British Columbia and elsewhere indicate that these in-tank suggestions have a unique "maintenance effect," retaining their power for months and, in several studies, years.
 

VISUALIZATION

The ability to create and manipulate internal imagery, called visualization, is one of the most powerful learning techniques at our disposal, increasing our ability to solve problems by "seeing" them in a new way, increasing our ability to remember by associating nonvisual information with visual cues, and, perhaps most important, enabling us to vividly rehearse or experience events mentally. Many studies have shown that an image held vividly in the mind tends to be perceived by the subconscious and the body as being real. Visualizing yourself skillfully performing some action, whether delivering a speech, hitting a perfect tennis backhand, or solving some problem, can be as effective as actually performing the action. The problem is that most of us find it hard to visualize performing a feat with the kind of total concentration and clarity necessary to convince our body it's a happening.

In the tank, however, you are free from all distractions and light. According to Dr. Glauberman, "Your ability to visualize is much more powerful while you're floating than it is even in hypnotic ice. Imagery seems more real, more dreamlike. Most of the time you're actually in the experience."

Dr. Rod Borrie, a New York City cognitive therapist who guides his clients through in-tank visualizations to help them increase learning, improve athletic and work performance, and change behavior patterns such as smoking and overeating, explains the effect in terms of information theory "The brain," he says, "can process only about seven bits of information at one time. Complex movements, such as athletic movements, are made of far more than seven bits of information at a time. Visualization puts all those bits in one chunk, like putting together a bunch of random letters, which would be impossible to remember, so they form a single word, which can be easily remembered. While floating, you put many actions together into a total image, so when the time comes to actually perform, the entire action is 'remembered' as a single image."

Just how real this "memory" can be is attested to by javelin thrower David Schmeltzer of the New York Pioneer Track Club, who uses in-tank visualization to "watch" himself throwing perfectly. Recently he surpassed his personal record by several feet, and recalls, "When I released the javelin on that day it was like deja' vu. At the point of release, I said, 'I know this throw, I've thrown this throw before!'"

The power of previsualization is not limited to relatively short actions, but can be used to rehearse mentally or "program" yourself for enormously complex situations with virtually infinite variables. For example, Bob Said, a former Grand Prix sports-car champion, who has led two Olympic bobsled teams and five U.S. World bobsled teams, described to me how he clearly visualized every foot of the bobsled run as he floated each morning while training for the 1984 Winter Olympic trials. "In the sled," he said, "you know where you want to be in each corner but often you find yourself someplace else. So you try to visualize all the different ways you can get into each corner, so that when you get into the corner you're already programmed for coming out." In sports, as in many life situations, we need to act rapidly, almost automatically. But too often we're paralyzed by the need to stop and think. For Said, the "muscle memory" that comes from repeated visualization frees him from that need: "If you have to think a reaction in the sled, even if you have the world's fastest reactions, you're too slow. The 'cleaner' you are, the faster you are. I'm definitely sharper from floating, but it's not a sharpening of abilities so much as it's allowing one's abilities to function the way they're supposed to, by getting rid of the clutter."

According to Borrie, who has worked with Glauberman in training a number of top-flight athletes by using in-tank visualization, "Every athlete we're working with who has competed has set a personal record. And they keep on setting them. It's just a very, very powerful tool." "Phenomenal," agrees Glauberman, "and it hasn't even begun to be tapped yet." They both emphasize that such learning through visualization is not limited to athletic performance - mental rehearsals like those of Said can be equally effective in complex situations such as performing surgery, giving a speech or presentation, or performing a role in a play or ballet.
 

ENHANCED LEARNING AND CREATIVITY

The results were startling. The float group learned significantly more than the nonfloat group on every level; but most important, as the degree of difficulty and complexity of the learning task increased, the superiority of floaters over nonfloaters increased sharply. Concluded Taylor, "There's no question that the [float] group learned more, but where they learned is the most important point. People who floated learned at a different cognitive level. The results show that the more difficult the concept, the bigger the difference in the performance of the two groups."

Interestingly, Taylor had tested the subject groups to see which were "visualizers" and which were "verbalizers," and concluded: "When the same learning records are analyzed on the basis of persons who are basically "visualizers" versus those who are primarily "conceptualizers" (nonvisual thinker), a greater degree of learning occurred in the visual than in the nonvisual group." While the number of visualizers in both groups was equal, Taylor noted that the float group appeared to visualize better than the nonfloat group. The EEGs indicated that the float group also produced significantly higher amounts of theta waves, which are associated with strong mental imagery. In summary, visualization enhances learning at all levels, floating increases visualization, floating's enhancement of ability increases as the complexity and difficulty of the material being learned increases, and floating sharply increases the ability to think creatively and synthetically. Floating seems to enhance mental functioning and open pathways of interaction between mind and body in so many ways that researcher Tom Fine of the Medical College of Ohio has called it "a breakthrough tool in psychobiology."
 

TANKS FOR THE MEMORIES: USING THE TANK FOR LEARNING

IN-TANK LEARNING

Most tank manufacturers now sell tanks with video monitors attached, so that floaters can relax until they are in a suitably receptive state, then turn on color videocassettes of visual material to be learned. Most commonly used thus far are commercially produced tapes of professional athletes playing at the peak of their form, demonstrating sports that include golf, tennis, running, downhill and cross-country skiing, racquetball, auto racing, soccer, baseball, basketball, football, sailing, and bowling. In a golf or tennis tape, for example, each type of swing is reproduced dozens of times for repetitive visual and sensory stimulation. The images are enhanced by sound - the solid sound of the club or racquet hitting the "sweet spot" - and computer-enhanced sequences that electronically highlight the flowing physical movements. Float-tank research at Stanford University indicates that watching such perfect performances has a "modeling" effect, causing you to absorb the movements in what has been called muscle memory programming, so that when you climb out of the tank the actual feel of the movements has been assimilated by your body. Watching a one-hour cassette is thought to be the equivalent of many hours of ideal physical practice.

Many athletes have made their own tapes. Professional football player Rafael Septien, a field- goal kicker for the Dallas Cowboys, is one example. Each day he climbs into the tank and watches images of himself kicking field goals. He credits this use of floating with helping him become an All-Pro kicker. "There's no doubt the tank is powerful," he told me. "They say that practice makes perfect, but actually it's perfect practice makes perfect. That's what you visualize in the tank - perfect practice." Other tapes have used the modeling effect to help train surgeons, musicians, salespeople, performers, visual artists, teachers, scientists, and business executives - whatever can be presented visually can be effectively presented to a floating learner. Says one maker of such training tapes, "Through recent advances in the neurological sciences, computerization, and solid- state sensing devices it is now possible to electronically transfer skills encoded on video software to the human nervous system." The possibilities of combining sight and sound seem virtually limitless and are only beginning to be explored.
 

POST-FLOAT LEARNING

This enhancement of mental and physical functioning makes the hours after a float ideal for learning of all sorts, since the mind is extremely receptive to external information, yet still in a somewhat free-floating state that is conducive to imaginative and creative thinking. Many floaters find that it is in the hours after a float that they find themselves discovering solutions to problems or being seized with new ideas, and often notice that this is a time when reading, studying, listening to music, and so on are particularly rewarding and productive.
 

PRE-FLOAT LEARNING

Shortly after that I was reading some reports of sensory-restriction research and read of a study in the early 1960s in which researchers read a lengthy passage from Tolstoy's War and Peace to two groups of subjects. They did not tell the subjects to remember this passage: in fact, it was just one of a number of events that occurred prior to the experiment. The subjects did not expect a retest. One group was a control group, and went about its normal activities: the other group spent a period in a sensory-restriction chamber. After twenty-four hours the two groups were retested. The researchers found that while there was a significant drop in retention for the control group, there was none for the experimental subjects. In fact, the sensory-deprivation group remembered more after twenty-four hours than at first! In interviewing the subjects, the researchers found that none of them had expected a retest, and only one had reported that he had even thought about the passage from War and Peace during the interim. The researchers dubbed this the "reminiscence effect." Somehow, simply being in a state of sensory restriction caused an increase in memory.

A recent series of experiments has cast some more light on this curious reminiscence effect. Subjects were given information, then one group consumed several ounces of alcohol - not enough to cause inebriation, but enough to put the subjects into a relaxed and somewhat euphoric state. The control group consumed no alcohol. When the two groups were later retested, it was found that the alcohol group had significantly greater recall of the information.

How to explain? Well, scientists now agree that there are at least two types of memory, generally known as short-term memory (STM) and long-term memory (LTM). When we are aware while driving of how many cars are behind us and how close they are, this is information being held in STM - ten miles down the road we will have forgotten it. When we look up a phone number and hold it in our minds for a few moments required to make the call, this too is the STM at work. STM, in short, deals with information we need to hold in our minds temporarily, but which is quickly forgotten. On the other hand, there is another type of information that can be held in consciousness just as fleetingly as, say, that telephone number, but can become so permanent that it can be recalled with absolute clarity a lifetime later, such as the memory of some brief event observed momentarily by a child but remembered ninety years later. This is information that has passed into LTM.

Studies using drugs that inhibit protein synthesis in the brain have proved that short-acting electrochemical changes in the brain represent STM while protein synthesis in the brain is necessary for LTM. When drugs that inhibit protein synthesis in the brain are given soon after subjects learn something, the information is forgotten - that is, it never makes it into LTM. However, when the drugs that inhibit protein synthesis are given more than an hour after the learning, the information is not forgotten, which means it has become a part of LTM. In other words, information passes in LTM- protein synthesis takes place in the brain - during the hour or two after the information is received.

One type of protein synthesis in the brain is structural growth: the growth of neurons, increasing numbers of glial cells, lengthening of dendrites, formation of new dendritic spines and synapses. As we have seen, this type of protein synthesis was first detected by Mark Rosenzweig, Marian Diamond, and their colleagues at UC Berkeley. They found that rats exposed to enriched environments exhibited heavier and thicker cortical layers, composed of larger neurons, more glial cells, longer dendrites, and more dendritic connections. Later studies have shown that even a few minutes of environmental enrichment are sufficient to cause permanent brain growth: that is, a brief experience of stimulation can result in protein synthesis. A study by William Greenough of the University of Illinois have shown that rats trained to run a maze show dendritic growth immediately after the training. That is, brain growth is specific response to learning.

Learning and long-term memory can occur only when protein synthesis takes place in the brain. Protein synthesis in the brain is a direct result of learning. That is, brain growth facilitates learning and memory on the one hand, and learning and memory lead to brain growth on the other hand. Memory and learning, in other words, cannot be separated from physical brain changes. Rosenzweig and colleagues proved that environmental enrichment leads to physical brain growth and increased memory and learning. Now we see that physical brain growth is essentially identical with the process of learning and increasing memory stores. To use Prigogine's terms, as energy enters the system in the form of new information or experiences, it can only be incorporated by means of actual change in the structure and organization of the system, that is, by brain growth. If something happens to stop this brain growth, such as administering a drug to inhibit protein synthesis, the new information that has entered the system will disappear, be forgotten. However, if sufficient time is allowed for this protein synthesis to take place, permanent changes will have taken place in the brain, and the information will be a part of long-term memory.

To return to the "reminiscence effect" noted by sensory-deprivation researchers, we can surmise that this effect results from the fact that after being given the information, the sensory- restriction group was removed for a period from new sensory input, from things that would compete with the information for long-term memory: Similarly, the alcohol group remembered more because in their slightly tipsy state they turned their brains off to potential new information to be remembered, thus giving the original information sufficient time to "solidify".

It seems clear that this reminiscence effect can be put to good use by floaters. Whatever information they want to put into long-term memory should be studied immediately prior to entering the tank (or should be presented via video or audio tapes during the early part of the float). The period of sensory restriction that follows - ideally at least an hour - should allow time for the necessary protein synthesis to occur in the brain to permit the information to become consolidated and committed to long-term memory.

Also, a number of float-tank studies have made it clear that floating has a vasodilatory effect, relaxing the tiny capillaries that carry blood into and throughout the brain. This results in a greater supply of blood to the individual neurons in the brain. Since blood carries the nutrients essential for protein, increased blood flow to the brain can only enhance protein synthesis. In the words of Dr. Arnold Scheibel, professor of medicine at UCLA and an expert on brain growth, "if there is a bottom line, it is that no neuron is healthier than the capillary that supplies it. And we have a very strong feeling that in the capillary supply system is the story of the maintenance or the slow decline" of the brain. The vasodilation that takes place while you are floating, then, facilitates brain growth, which means that by increasing blood flow to the brain floating can facilitate learning and the formation of long-term memory.